Method of construction utilizing inflatable fluid containers



June 12, 1956 K. o. VARTIA 2,749,592

METHOD OF CONSTRUCTION UTILIZlNG INFLATABLE FLUID CONTAINERS Filed June 26, 1952 KM (0M1 1 N VllN TOR.

United States Patent Oflice 2,749,592 Patented June 12, '1956 METHOD OF CONSTRUCTION UTILIZING INFLAT- ABLE FLUID CONTAINERS Karl O. Vartia, Austin, Tex.

Application June 26, 1952, Serial No. 295,702

6 Claims. (Cl. 25-155) My invention relates to a simple and economical method of constructing concrete walls or the like with out the necessity of erecting expensive forms for eastin-place concrete nor the requirement for heavy equipment to move or tilt precast slabs into place. It is relatively cheap to cast a slab of concrete or the like in a horizontal position at ground level. This fact has been recognized and utilized in the so-called tilt-up slab method of wall construction in which wall slabs are cast upon a floor slab or other suitable area adjacent to their final position and when sufficiently strong for handling are raised to erect position. One objection to the method is the fact that the slab must develop fairly high strength before being moved in order to resist the concentrated loadings incident thereto. Another is the necessity of bringing to the building site at considerable cost a heavy crane or the like for a relatively short period of useful operation. My invention substitutes for the heavy lifting equipment a fluid container which is deflated and laid upon the floor slab, and upon which the wall slab is then cast. When the concrete of the Wall slab has set, the container is inflated to lift the slab and swing it into place.

This form of the invention is illustrated in Fig. 1 of the attached drawings. Upon floor slab 1 there is placed a deflated pneumatic container 2. Slab 3 will then be formed by any desired method such as placing edge forms and pouring a monolithic slab, or by assembling the larger unit from a number of smaller precast units suitably tied together. Approximately at point A there will be provided an anchoring arrangement permitting the slab to pivot but not shift otherwise to any substantial extent. The pivoting anchorage might consist of conventional two-plate hinges having one plate secured to floor slab 1 and the other to wall unit 3, or might comprise separable hinge elements with one element adapted to be anchored into floor slab 1 during its fabrication and with the complementary unit to be secured to wall unit 3 during or after the fabrication of the latter. Possibly the simplest and most economical hinge arrangement would be a series of heavy wire loops or hairpin shapes embedded in slab 1, but exposed at the surface adjacent to point A by scooping out enough concrete adjacent to each loop during finishing operations to permit passing another length of wire through the loop. The latter wire would be bent and anchored in the wall unit during its fabrication. In the case of a poured wall unit, the scooped out depressions adjacent to the loops may be filled with sand to provide a level surface prior to pouring the wall unit. Alternatively, the vertical restraint to cause tilting of wall unit 3 might be provided by temporary weights placed upon the wall unit adjacent to point A. After the wall unit has begun to tilt, the pressure within container 2 creates a lateral thrust against the Wall unit, but if the container is secured to unit 3 adjacent to point A this thrust is balanced out. If the container 2 is made of smooth plastic material it will probably be necessary in any case to secure it either to the floor slab 1 or the wall unit 3,

or both, to prevent its sliding out of the corner during later stages of inflation. A cable 4 may be used to assist in raising the wall slab after it has reached a point Where a horizontal force can be effective. Cable 5 likewise may be used to control the position of the Wall, and 4 and 5 together may be used to anchor the wall in erect position while permanent anchorages such as transverse walls or diaphragms are being constructed.

In Fig. 2 is illustrated another use of containers 2. It may be desirable to cast a wall slab in a location somewhat removed from the final tilt-up position. For instance, one wall slab adjacent a corner may be formed and erected as in Fig. 1. Simultaneously, another slab 3 may be formed on the floor slab just beyond the area occupied by the first slab. In this case the slab 3 may be lifted, after being formed, by container 2 and then rolled onto a second container 2 which will be suitably inflated to effect a smooth transition of the weight of slab 3 from one pneumatic container to the other. By deflating the second container 2 the slab may be lowered for fastening to the floor slab at point A and then tilted to erect position as in Fig. l. The transition from one container to another may be repeated as often as necessary to cover the distance between the casting or forming location and the desired final position.

In Fig. 3 is illustrated another form of my invention. Preferably by placing several deflated containers 6 one upon the other on the floor slab 1 before forming slab 7 and then inflating them, slab 7 may be raised vertically to an elevated position as a roof slab. Column or other supports would be placed under the edges of the slab, and the containers then deflated and removed. The containers may be made doughnut-shaped for greater stability and to minimize bending moment at the center of the slab due to the overhang of the edges. Also, the containers may be inflated from the flat to the extended condition shown in Figure 3 in sequence to minimize the extent of the less stable, partially-inflated condition. For a roof slab unit of greater area, several stacks of containers 6 could be used in spaced relationship to obtain any required distribution of support with adequate stability. Column supports or the like would be placed as required under the accessible areas of the slab between the supporting containers and the containers then deflated to transfer the load to these other supports.

I wish to note that while it appears most practicable to use air as an inflating medium for the containers 2, some other gaseous fluid or, perhaps, liquid could be used to effect the purposes of my invention.

I claim:

1. A method of construction which comprises forming a unit of a structure upon a substantially deflated fluid container, moving the unit to another position by inflating the fluid container, transferring the weight of said unit to other supporting means, and then deflating and removing said fluid container.

2. A method of construction which comprises forming a unit of a structure upon a series of deflated fluid containers, moving the unit to another position by inflating the fluid containers, transferring the weight of said unit to other supporting means, and then deflating and removing said fluid containers.

3. A method of constructing a wall which comprises placing a deflated fluid container upon a substantially horizontal area adjacent to said wall location, forming a section of said wall in a substantially horizontal position upon said deflated fluid container, restraining one edge of said section against substantial vertical or horizontal translation, inflating said fluid container to create a lifting force upon said section of Wall and cause it to be tilted into erect position, providing means to hold said section of wall in erect position, and deflating and removing said container.

4. A method of constructing a substantially vertical slab which comprises forming a slab in a substantially, horizontal position upon a deflated fluid container, restraining one edge of said slab against substantial vertical or horizontal movement, inflating said fluid container to cause said slab to tilt toward vertical position, providing alternate means to retain said slab in its altered position, and deflating and removing said container from operative relationship with said wall unit.

5. A method of construction which comprises placing upon a suitable forming area a container capable of being inflated with air or other fluid and of retaining said fluid for a substantial time, causing said container to be deflated so that a load placed upon said container Will cause the upper fabric of said container to contact the lower fabric and thus transfer through solid contact the Weight of said load to the area beneath the container, fabricating upon said container in solid supported relationship with the area beneath said container a structure capable of being moved as a unit, inflating said container to cause said structure to be supported by fluid pressure and to be moved to another position, securing said structure in supported relationship upon solid supports in, said other position, and then deflating and removing said container.

6. A method of construction which comprises placing upon a suitable forming area a series of containers capable of being inflated with air or other fluid and of retaining said fluid for a substantial time, causing said containers to be deflated so that a load placed upon said containers will cause the adjacent layers of fabric of said containers to come into supporting contact and thus transfer through solid contact the weight oftsaidtload to the area beneath the containers, fabricating upon said containers in solid supported relationship with the area beneath said containers a structure capable, of being moved as a unit, inflating said containers to cause said structure to be supported by fluid pressure and to be moved to another position, securing said structure in supported relationship upon solid supports in said other position, and then deflating and removing said containers,

References Cited in the file of this patent UNITED STATES PATENTS 889,083 Aiken May 26, 1908 1,386,417 Marx Aug. 2, 1921 1,668,299 Aiken May 1, 1928 2,140,325 Morse Dec. 13, 1933 2,226,201 Freyssinet Dec. 24, 1940 2,495,092 Cox et al Jan. 17, 1950 2,541,928 Loomis Feb. 13, 1951 

